Mask



FIG. 1 is a perspective view of a mask showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is a bottom-front-left perspective view thereof;

FIG. 9 is a bottom-front-right perspective view thereof;

FIG. 10 is a top-front-left perspective view thereof;

FIG. 11 is a bottom-rear-left perspective view thereof;

FIG. 12 is a bottom-rear-right perspective view thereof;

FIG. 13 is a top-rear-left perspective view thereof; and,

FIG. 14 is a top-rear-right perspective view thereof.

CLAIM The ornamental design for a mask, as shown and described.